Let’s take a closer look at the two matchups and dig into a couple predictions.

Caroline Wozniacki vs. Shuai Peng

Charles Krupa/Associated Press

While the other semifinal features a 17-time Grand Slam winner, neither Wozniacki nor Peng has won a major in their career.

Wozniacki has certainly come painfully close at Flushing Meadows, though. She reached the U.S. Open finals in 2009 but lost to Kim Clijsters, and she made it to the semifinals in 2010 and 2011. Peng, on the other hand, has never made it to a semifinal at any Grand Slam.

Wozniacki, who is a former No. 1 player, may be primed to finally get that elusive Grand Slam title. She outlasted Maria Sharapova in something of an upset in a grueling three-set battle and easily handled Sara Errani in straight sets Tuesday. Wozniacki has always been known as a superb defensive player, but she was the aggressor in both matches.

Kathy Willens/Associated Press

In fact, it took her all of 65 minutes to eliminate Errani.

SI Tennis noted that Wozniacki is hitting winners to go along with her impressive defense:

SI Tennis @SI_Tennis

Caroline Wozniacki is into a Slam semifinal for the first time since the 2011 US Open. Trounces Sara Errani 60 61. Hit *26* winners.

On the other side is Peng, who hasn’t lost a set at the U.S. Open. She is a formidable net player from her days as a former No. 1 in doubles and can force the issue up close.

However, Wozniacki has only lost once to Peng in her career, and that came back in 2007 when she was just a teenager. Wozniacki is more battle-tested and has the experience edge on tennis’ brightest stages. Peng hasn’t even been in a close match yet, so Wozniacki should have the mental edge if the proceedings get tight down the stretch.

Look for Wozniacki to take one more step toward that Grand Slam.

Prediction: Wozniacki in straight sets

Serena Williams vs. Ekaterina Makarova

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Williams has been the dominant force at the U.S. Open since the tournament began, and that’s not about to change Friday.

She is the two-time defending champion, has made the semifinals four years in a row, has five overall U.S. Open titles and is trying to become the first woman to win three straight at Flushing Meadows since 1978.

What’s more, she is playing better than she has all season and is in her first major semifinal of the year. She hasn’t dropped a set and hasn’t even lost more than three games in a single set. She also demonstrated that she is capable of turning on a switch at any moment when she lost the first three games of her quarterfinal match against Flavia Pennetta but won 12 of the next 14 to secure the match.

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Don’t overlook Makarova, though. She picked up her first-ever Grand Slam quarterfinal victory against Victoria Azarenka in straight sets and already beat Williams at this year’s U.S. Open in the doubles tournament.

She talked about the upcoming match with Williams, via David Satriano of the New York Post:

Well, she’s a great and tough player. But once I beat her already, so I have a great memory. I have a great feeling of that match.

Definitely [have] to stay aggressive, because she’s so aggressive. And I need to be a little bit more aggressive than she is.

Despite the doubles victory, Williams is 3-1 in her singles career against Makarova and beat her at the 2012 U.S. Open in straight sets. She is also far more experienced on the big stage and will look to control Friday’s showdown from the onset with her powerful serve.

Look for Williams to do just that and set up a marquee matchup in the finals against Wozniacki.